International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B4. Istanbul 2004
Upon entering the data of the topographic characteristics by
[n order to resolve problems relating to incorrect or implementing the specific technology of superposition, the
missing height data are connected with creating of photogrammetis (operator) visually Scans. the model in
preliminary DEM implementation bf all regarding to corrections in the image or additions by means
photogrammetrically defined points of the model, and of comparing history maps of the terrain characteristics to
supplemented by the height values of the existing DTM or the stereo-model. The amendments in the terrain are
file of the contour lines. The first step is to establish the identified and depicted in order to represent the track Yi
density of the network covered and crossed by two- between the prior and the new contour. All existing vectors
dimensional indexed contour lines, and also checking of the and points within the surrounded region are deleted and
first DEM iteration. From this point of view the heights are replaced by points acquired by means of photogrammetric
related to the indexed contour lines of the nearest 30 m. methods. Besides that the regional amendments could be
Depending on the quality of the original data, the search for identified by means of tracking all suspicious peculiarities,
correlating index contour lines is allowed up to 60 m, if The contour lines and the updated regions are generated by KEY V
appropriate. means of. new sets of points and interrupted lines,
implementing triangular asymmetrical network. For editing
whole maps a wide-scope processing of data is used. What
The new generation of DEM proposes as a milestone basis mentioned above is a stage at which for the purposes of ABSTI
the combination of survey photography details required for automatic editing and magnification of the data
the photogrammetric update. To generate topologically presentation, an extensional software is used to develop the Nowad
correct contour lines the system implements automatic map topology and secure data continuity. want tc
processes for closing gaps and deleting overlapping linear routes.
segments in the Contour lines. Some planimetric Inform
displacements of the contour lines that could be caused by In order to check up Whether all data are correctly carried
the graphical editing or mapping deformation, cause converted, GIS specialists test the files on graphic It is lil
additional errors in the DEM that could not be corrected. workstations. will be
The existing heights may be implemented as an indicator fnis s
for the accuracy of the contour lines and of the DEM as a Conclusion Metror
whole. The height data could be analysed in order to define
whether the acquired data are correct. The co-ordination ^ The points that have been highlighted in this reports have
values of the stipulated planimetric peculiarities, such as concluded that there can one approach that can be adopted in
hydrological peculiarities, routes of roads, etc. are finding a new, systematic and direct solution in utilizing the There
compared with the DTM file. In case this could be appropriate tools which allow far accurate data collection, case recent]
performed the planimetric characteristics will be of data accumulation, as well as increases in the efficiency in fields:
reclassified as interrupted lines. the semiautomatic 3D data acquisition . count
: A netv
Updating Maps References GIS.
: s railway
1. Amhar, F.,V. Ecker. 1996 a. An Integrated Solution for the school
In order to make changes and to perform updating, Problems of 3D Man-Made Objects in Digital Orthophotos. distriy
concurrently with the existing stereoscopic data new aero- ISPRS XVIII Congress, Vienna. Intern. Archive of and x
photographic survey shall be considered. The updating of Photogrammetry and Remote Sensing, Vol XXXI, Part B4, infrast
the map is performed only in case when the reconsidered Commission IV. she mo
corrections could be defined by some stereoscopic method. 2. Haidoushki, I. 1978. Photogrammetry. Sofia,” Tehnika, flow 6
Bulgaria. inform
The operations on updating the map of the existing vector 3. KS I; L. Ke a ef EK pu
or point data of the aero-photographic survey, require the Topographie dap in Bulgacia ISBRS "ONsress, em Netwo
following steps: Intern. Archive of Photogrammetry and Remote Sensing, Vo hetwal
XXXI, Part B4, Commission IV.
* Photo-interpretation. 4. Kraus, K. Photogrammetry, Vol. 2. Bonn, Ferd.Duemmler rans
e Establishing the corrections. Verlag, 1997. model
e Acquisition of new data. 5. Lang, F., Locherbach, T., Chickler,W., 1995. A One-Eye Toutes,
e Database integration of history and new data. Stereo System for Semi-automatic 3D-Building Extraction. analyz
GIM, June 1995,pp.6-8. planum
One of the effective methods for the retrieval the 6. Malla, A. 1999. Photogrammetric methods for creation and ar
new data is by means of superposing of existing digital data renovation of large scale maps. Sofia, Geodesija, Kartograf1ja, vn
onto the existing new aero-photo survey, and updating the Zemeustrojstvo, 1,Bulgaria. : of ner
database by means of acquiring new data from the stereo- 7. Malla, A. 1999. Expedient Photogrammetric methods and etwor
models. The superposition and acquisition of data could be technologies for generation of cadastral maps and plane. Sofia, N
represented in various ways. The updating of the map or its Geodesija, Kartografija, Zemeustrojstvo, 4, Bulgaria. EURO
modification could be regarded to change in the thematic the s
description, to changes in the Z co-ordinate (height), or by Netwo
means of amending the dislocation of X and Y co-ordinates. along :
on nu
route,”
betwee
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